The Animal Core will provide support and funding for the animal related activities for Projects I, II and III. The creation of the Core is a direct response to the increased use of various rodent strains for in vivo studies of the molecular biology of tissue factor. The extensive use of transgenic and knockout animals (generated by other investigators and ourselves) demands careful breeding, documentation and genotyping of offspring. Currently, PAR-1-/-, Factor V Leiden, mTF+/- and transgenic and rescued mice containing the human TF minigene, and its derivatives, are maintained by the Core. The Core will be responsible for the maintenance of these and other lines, distribution of animals to the various projects and generating new lines by breeding and genotyping. The consolidation of all research animal support into a single Core to supervise the conduct of the specific approval protocols of the Program Project has been reviewed and approved by the institutional Animal Research Committee.